Method, Terminal Device and Network Device for Time Advance Adjustment

ABSTRACT

Methods, network device and terminal device are disclosed time advance adjustment. A method comprises receiving a time advance, TA, command from a network device; determining a TA granularity or range; and determining a TA value based at least partly on the TA command and the TA granularity or range, wherein different numerologies are configured for at least two carriers and/or at least two bandwidth parts (BWPs) in one carrier, wherein the at least two carriers and/or the at least two BWPs serve the terminal device and/or the terminal device supports at least one numerology.

TECHNICAL FIELD

Embodiments of the disclosure generally relate to wirelesscommunication, and, more particularly, to method, network device andterminal device for time advance (TA) adjustment.

BACKGROUND

TA is used in certain wireless networks such as Global System for MobileCommunications (GSM) and Long Term Evolution (LTE). Orthogonality in theuplink may be either partly or fully achieved by separating the usertransmissions in the time domain. In order to maintain such separation,a network device may need to receive the transmissions from variousdevices connected to a given network at substantially the time thetransmissions would be expected if there were no propagation delay. Inthe case of LTE and GSM, such reception is ensured by means of aprocedure known as the TA.

For example, in the radio resource control (RRC) connected mode in LTE,E-UTRAN Node B (cNB) is responsible for maintaining the uplink timingthrough the timing advance procedure. The uplink timing of a userequipment (UE) is measured by the cNB using a physical random accesschannel (PRACH) and/or a periodic sounding reference signal (SRS)transmitted by the UE. Periodic timing advance commands are transmittedby the eNB to maintain the uplink timing based on the received SRSsignals. In the case of LTE, a UE knows when it is uplink synchronizedand when it is not, based on a timer whose value is set by the network.While the time alignment timer is running, the LTE UE is considered tobe in a synchronized state. The timer is restarted when a new timingadvance command is received from the eNB. When a UE is not uplinksynchronized, the UE is forced to release all synchronous uplinkresources and initiates an uplink transfer only after a RACH procedure,upon which the uplink timing is re-attained.

SUMMARY

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

It is noted that GSM/LTE only supports a single numerology operation ina carrier and a fixed TA adjustment configuration. Recently, multiplenumerology operation in a carrier in a new radio (NR) system was agreedin RAN1 of 3GPP (the 3rd Generation Partnership Project). However, thefixed TA adjustment configuration used in a wireless network supportingsingle numerology operation such as LTE-GSM might not suit the wirelessnetworks supporting multiple numerology operation very well. Therefore,it would be desirable to provide a solution for TA adjustment in thenetworks supporting multiple numerology operation.

According to an aspect of the disclosure, it is provided a method foroperating a terminal device. The method may comprise: receiving a timeadvance, TA, command from a network device; determining a TAgranularity; and determining a TA value based at least partly on the TAcommand and the TA granularity. Different numerologies may be configuredfor at least two carriers, wherein the at least two carriers serve theterminal device and the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofthe multiple numerologies used by the terminal device, wherein there isa correspondence between numerology and TA granularity.

In an embodiment, the numerology comprises the subcarrier spacing, SCS.

In an embodiment, determining the TA value based at least partly on theTA command and a TA granularity comprises: updating a previous TA valueconsidering the difference between an old TA granularity and a new TAgranularity; calculating a TA compensation based on the new TA commandand the new TA granularity; and determining the TA value based on theupdated TA value and the TA compensation.

According to another aspect of the disclosure, it is provided a methodfor operating a terminal device. The method may comprise: receiving atime advance, TA, command from a network device: determining a TAgranularity; and determining a TA value based at least partly on the TAcommand and the TA granularity. The TA granularity is determined by anumerology of multiple numerologies used by the terminal device, whereinthere is a correspondence between numerology and TA granularity.

In an embodiment, wherein different numerologies are configured for atleast two carriers, wherein the at least two carriers serve the terminaldevice and the terminal device supports multiple numerologies.

In an embodiment, wherein the numerology comprises the subcarrierspacing, SCS.

In an embodiment, determining the TA value based partly on the TAcommand and a TA granularity comprises: updating a previous TA valueconsidering the difference between an old TA granularity and a new TAgranularity; calculating a TA compensation based on the new TA commandand the new TA granularity; and determining the TA value based on theupdated TA value and the TA compensation.

According to another aspect of the disclosure, it is provided a methodfor operating a terminal device. The method comprises receiving a TAcommand from a network device; determining a TA granularity or range;and determining a TA value based at least partly on the TA command andthe TA granularity or range, wherein different numerologies areconfigured for at least two carriers and/or at least two bandwidth parts(BWPs) in one carrier, wherein the at least two carriers and/or the atleast two BWPs serve the terminal device and the terminal devicesupports at least one numerology.

In an embodiment, the TA granularity or range is determined by one ormore of a cyclic prefix (CP) length, a numerology and a carrierfrequency used by the terminal device, wherein there is a correspondencebetween CP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the method further comprises receiving a messagecontaining the TA granularity or range from the network device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

In an embodiment, determining the TA value based on one or more of theTA command and a TA granularity or range comprises: updating a previousTA value considering the difference between an old TA granularity orrange and a new TA granularity or range; calculating a TA compensationbased on the new TA command and the new TA granularity or range; anddetermining the TA value based on the updated TA value and the TAcompensation.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the method further comprisesdetermining the format of the TA command based on the TA granularity orrange.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is received together with uplink grantor a medium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused for the UI grant or a numerology of the PUSCH (Physical UplinkShared Channel) scheduled by the UL grant.

In an embodiment, the numerology comprises at least one of thefollowings: the subcarrier spacing, SCS, the Bandwidth Part, BWP.

According to another aspect of the disclosure, it is provided a methodfor operating a network device. The method comprises determining a timeadvance, TA, value for a terminal device; determining a TA granularityfor the terminal device; generating a TA command based on the TA valueand the TA granularity; and sending the TA command to the terminaldevice. Different numerologies may be configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofthe multiple numerologies used by the terminal device, wherein there isa correspondence between numerology and TA granularity.

In an embodiment, the numerology comprises the subcarrier spacing, SCS.

According to another aspect of the disclosure, it is provided a methodfor operating a network device. The method comprises determining a timeadvance, TA, value for a terminal device; determining a TA granularityfor the terminal device; generating a TA command based on the TA valueand the TA granularity; and sending the TA command to the terminaldevice. The TA granularity is determined by a numerology of multiplenumerologies used by the terminal device, wherein there is acorrespondence between numerology and TA granularity.

In an embodiment, different numerologies arc configured for at least twocarriers. The at least two carriers serve the terminal device and theterminal device supports multiple numerologies.

In an embodiment, the numerology comprises the subcarrier spacing. SCS.

According to another aspect of the disclosure, it is provided a methodfor operating a network device. The method comprises determining a TAvalue for a terminal device; determining a TA granularity or range forthe terminal device; generating a TA command based on the TA value andthe TA granularity or range; and sending the TA command to the terminaldevice, wherein different numerologies are configured for at least twocarriers and/or at least two bandwidth parts (BWPs) in one carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

In an embodiment, the TA granularity or range is determined by at leastone of a cyclic prefix (CP) length, a numerology and a carrier frequencyused by the terminal device, wherein there is a correspondence betweenCP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the method further composes sending a messagecontaining the TA granularity or range to the terminal device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, the reference numerology for a TAG is determined basedon the operating numerologies of all carriers belonging to the TAG. Forinstance, the numerology with the largest subcarrier spacing and/orshortest CP length among the said operating numerologies can bedetermined as reference numerology for the TAG.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the method further comprisesdetermining the format of the TA command based on the TA granularity orrange.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is sent together with uplink grant or amedium access control (MAC) command associated with uplink grant whereinthe TA granularity or range is determined based on a numerology used forthe UL grant.

In one embodiment the TA command is sent together with uplink grant or amedium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyof the PUSCH scheduled by the UL grant.

In one embodiment the numerology comprises at least one of thefollowings: the subcarrier spacing, SCS, the Bandwidth Part, BWP.

According to another aspect of the disclosure, it is provided a terminaldevice, comprising: n processor, and a memory, the memory containinginstructions executable by the processor, whereby the terminal device isoperative to: receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity. Different numerologiesare configured for at least two carriers, wherein the at least twocarriers serve the terminal device and the terminal device supportsmultiple numerologies.

According to another aspect of the disclosure, it is provided a terminaldevice, comprising: a processor; and a memory, the memory containinginstructions executable by the processor, whereby the terminal device isoperative to: receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity. The TA granularity isdetermined by a numerology of multiple numerologies used by the terminaldevice. Then; is a correspondence between numerology and TA granularity.

According to another aspect of the disclosure, it is provided a terminaldevice, comprising: a processor, and a memory, the memory containinginstructions executable by the processor, whereby the terminal device isoperative to: receive a TA command from a network device; determine a TAgranularity or range; and determine the TA value based at least partlyon the TA command and the TA granularity or range, wherein differentnumerologies are configured for at least two carriers and/or at leasttwo bandwidth parts (BWPs) in one carrier, wherein the at least twocarriers and/or the at least two BWPs serve the terminal device and theterminal device supports at least one numerology.

According to another aspect of the disclosure, it is provided a networkdevice, comprising: a processor; and a memory, the memory containinginstructions executable by the processor, whereby the network device isoperative to: determine a time advance, TA, value for a terminal device;determine a TA granularity for the terminal device; generate a TAcommand based at least partly on the TA value and the TA granularity;and send the TA command to the terminal device. Different numerologiesare configured for at least two carriers. The at least two carriersserve the terminal device and the terminal device supports multiplenumerologies.

According to another aspect of the disclosure, it is provided a networkdevice, comprising: a processor, and a memory, the memory containinginstructions executable by the processor, whereby the network device isoperative to: determine a time advance, TA, value for a terminal device;determine a TA granularity for the terminal device; generate a TAcommand based on the TA value and the TA granularity; and send the TAcommand to the terminal device. The TA granularity is determined by anumerology of multiple numerologies used by the terminal device, whereinthere is a correspondence between numerology and TA granularity.

According to another aspect of the disclosure, it is provided a networkdevice, comprising: a processor; and a memory, the memory containinginstructions executable by the processor, whereby the network device isoperative to: determine a time advance, TA, value for a terminal device;determine a TA granularity or range for the terminal device; generate aTA command based at least partly on the TA value and the TA granularityor range; and send the TA command to the terminal device. Differentnumerologies are configured for at least two carriers and/or at leasttwo bandwidth parts (BWPs) in one carrier. The at least two carriersand/or the at least two BWPs serve the terminal device and the terminaldevice supports at least one numerology.

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity. Different numerologiesare configured for at least two carriers, wherein the at least twocarriers serve the terminal device and the terminal device supportsmultiple numerologies

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity. The TA granularity isdetermined by a numerology of multiple numerologies used by the terminaldevice. There is a correspondence between numerology and TA granularity.

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to receive a TA command from a network device; determine a TAgranularity or range; and determine the TA value based at least partlyon the TA command and the TA granularity or range, wherein differentnumerologies are configured for at least two carriers and/or at leasttwo bandwidth parts (BWPs) in one carrier, wherein the at least twocarriers and/or the at least two BWPs serve the terminal device and theterminal device supports at least one numerology.

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to determine a time advance, TA, value for a terminal device;determine a TA granularity for the terminal device; generate a TAcommand bused at least partly on the TA value and the TA granularity;and send the TA command to the terminal device. Different numerologiesare configured for at least two carriers. The at least two carriersserve the terminal device and the terminal device supports multiplenumerologies.

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to determine a time advance, TA, value for a terminal device;determine a TA granularity for the terminal device; generate a TAcommand based on the TA value and the TA granularity; and send the TAcommand to the terminal device, wherein the TA granularity is determinedby a numerology of multiple numerologies used by the terminal device,wherein there is a correspondence between numerology and TA granularity.

According to another aspect of the disclosure, it is provided a computerprogram product. The computer program product comprises instructionswhich when executed by at least one processor, cause the at least oneprocessor to determine a time advance, TA, value for a terminal device;determine a TA granularity or range for the terminal device; generate aTA command based at least partly on the TA value and the TA granularityor range; and send the TA command to the terminal device, whereindifferent numerologies are configured for at least two carriers and/orat least two bandwidth parts (BWPs) in one carrier, wherein the at leasttwo carriers and/or the at least two BWPs serve the terminal device andthe terminal device supports at least one numerology.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to receive a time advance, TA, command from anetwork device; determine a TA granularity; and determine a TA valuebased at least partly on the TA command and the TA granularity.Different numerologies are configured for at least two carriers, whereinthe at least two carriers serve the terminal device and the terminaldevice supports multiple numerologies.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to receive a time advance, TA, command from anetwork device; determine a TA granularity; and determine a TA valuebased at least partly on the TA command and the TA granularity. The TAgranularity is determined by a numerology of multiple numerologies usedby the terminal device. There is a correspondence between numerology andTA granularity.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to receive a TA command from a network device;determine a TA granularity or range; and determine the TA value based atleast partly on the TA command and the TA granularity or range, whereindifferent numerologies are configured for at least two carriers and/orat least two bandwidth parts (BWPs) in one carrier, wherein the at leasttwo carriers and/or the at least two BWPs serve the terminal device andthe terminal device supports at least one numerology.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to determine a time advance, TA, value for aterminal device; determine a TA granularity for the terminal device;generate a TA command based at least partly on the TA value and the TAgranularity; and send the TA command to the terminal device. Differentnumerologies are configured for at least two carriers. The at least twocarriers serve the terminal device and the terminal device supportsmultiple numerologies.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to determine a time advance, TA, value for aterminal device; determine a TA granularity for the terminal device;generate a TA command based on the TA value and the TA granularity; andsend the TA command to the terminal device, wherein the TA granularityis determined by a numerology of multiple numerologies used by theterminal device, wherein there is a correspondence between numerologyand TA granularity.

According to another aspect of the disclosure, it is provided a computerreadable storage medium. The computer readable storage medium comprisesinstructions which when executed by at least one processor, cause the atleast one processor to determine a time advance, TA, value for aterminal device; determine a TA granularity or range for the terminaldevice; generate a TA command based at least partly on the TA value andthe TA granularity or range; and send the TA command to the terminaldevice, wherein different numerologies are configured for at least twocarriers and/or at least two bandwidth parts (BWPs) in one carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

According to another aspect of the disclosure, it is provided a methodimplemented in a communication system including a host computer, a basestation and a user equipment. The method may comprise at the hostcomputer, receiving user data originating from a transmission from auser equipment to a base station. The base station is operative toperform the method associated with network device according to any oneof embodiments of present disclosure. The user equipment is operative toperform the method associated with user equipment according to any oneof embodiments of present disclosure.

According to another aspect of the disclosure, it is provided a methodimplemented in a communication system including a host computer, a basestation and a user equipment, the method comprising: at the hostcomputer, initiating a transmission carrying user data to the userequipment via the base station. The base station is operative to performthe method associated with base station according to any one ofembodiments of present disclosure. The user equipment is operative toperform the method associated with user equipment according to any oneof embodiments of present disclosure.

According to another aspect of the disclosure, it is provided acommunication system including a host computer comprising: a processingcircuitry configured to provide user data; and a communication interfaceconfigured to receive user data originating from a transmission from auser equipment to a base station. The base station comprises a processorand a memory, the memory containing instructions executable by theprocessor, whereby the base station is operative to perform the methodassociated with base station according to any one of embodiments ofpresent disclosure. The user equipment comprises a processor and amemory, the memory containing instructions executable by the processor,whereby the user equipment is operative to perform the method associatedwith user equipment according to any one of embodiments of presentdisclosure.

According to another aspect of the disclosure, it is provided acommunication system including a host computer comprising: a processingcircuitry configured to provide user data; and a communication interfaceconfigured to initiate a transmission carrying user data to a userequipment via a base station. The base station comprises a processor anda memory, the memory containing instructions executable by theprocessor, whereby the base station is operative to perform the methodassociated with base station according to any one of embodiments ofpresent disclosure. The user equipment comprises a processor and amemory, the memory containing instructions executable by the processor,whereby the user equipment is operative to perform the method associatedwith user equipment according to any one of embodiments of presentdisclosure.

These and other objects, features and advantages of the disclosure willbecome apparent from the following detailed description of illustrativeembodiments thereof, which are to be read in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a schematic system, in which some embodiments of thepresent disclosure can be implemented;

FIG. 2 shows an example of multiple BWP configurations in one carrier;

FIG. 3 is a diagram depicting Timing Advance Command MAC controlelement;

FIG. 4 is a flow chart depicting a method according to an embodiment ofthe present disclosure;

FIG. 5 shows four formats for TA command signaled in MAC CE according toan embodiment of the present disclosure;

FIG. 6a is flow chart depicting a method according to an embodiment ofthe present disclosure;

FIG. 6b is flow chart depicting a method according to another embodimentof the present disclosure;

FIG. 7 is a flowchart illustrating methods on both a network device'sside and a terminal device's side according to an embodiment of thedisclosure;

FIG. 8 is a block diagram illustrating a network device according to anembodiment of the disclosure;

FIG. 9 is a block diagram illustrating a terminal device according to anembodiment of the disclosure;

FIG. 10 is a block diagram illustrating a network device according to anembodiment of the disclosure;

FIG. 11 is a block diagram illustrating a terminal device according toan embodiment of the disclosure;

FIG. 12 is a block diagram illustrating a telecommunication networkconnected via an intermediate network to a host computer in accordancewith some embodiments of the present disclosure;

FIG. 13 is a block diagram illustrating a host computer communicatingvia a base station with a UE over a partially wireless connection inaccordance with some embodiments of the present disclosure;

FIG. 14 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure;

FIG. 15 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure; and

FIG. 16 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure; and

FIG. 17 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure.

DETAILED DESCRIPTION

For the purpose of explanation, details are set forth in the followingdescription in order to provide a thorough understanding of theembodiments disclosed. It is apparent, however, to those skilled in theart that the embodiments may be implemented without these specificdetails or with an equivalent arrangement.

As used herein, the term “wireless communication network” refers to anetwork following any suitable communication standards, such asLTE-Advanced (LTE-A), LIE, Wideband Code Division Multiple Access(WCDMA), High-Speed Packet Access (HSPA), and so on. Furthermore, thecommunications between a terminal device and a network device in thewireless communication network may be performed according to anysuitable generation communication protocols, including, but not limitedto. Global System for Mobile Communications (GSM). Universal MobileTelecommunications System (UMTS), Long Term Evolution (LTE), and/orother suitable, and/or other suitable the first generation (1G), thesecond generation (2G), 2.5G, 2.75G, the third generation (3G), thefourth generation (4G), 4.5G, the future fifth generation (5G)communication protocols, wireless local area network (WLAN) standards,such as the IEEE 802.11 standards; and/or any other appropriate wirelesscommunication standard, such as the Worldwide Interoperability forMicrowave Access (WiMax), Bluetooth, and/or ZigBee standards, and/or anyother protocols either currently known or to be developed in the future.

The term “network device” refers to a device in a wireless communicationnetwork via which a terminal device accesses the network and receivesservices therefrom. The network device refers a base station (BS), anaccess point (AP), or any other suitable device in the wirelesscommunication network. The BS may be, for example, a node B (NodeB orNB), an evolved NodeB (eNodeB or eNB), or gNB, a Remote Radio Unit(RRU), a radio header (RH), a remote radio head (RRH), a relay, a lowpower node such as a femto, a pico, and so forth. Yet further examplesof the network device may include multi-standard radio (MSR) radioequipment such as MSR BSs, network controllers such as radio networkcontrollers (RNCs) or base station controllers (BSCs), base transceiverstations (BTSs), transmission points, transmission nodes. Moregenerally, however, the network device may represent any suitable device(or group of devices) capable, configured, arranged, and/or operable toenable and/or provide a terminal device access to the wirelesscommunication network or to provide some service to a terminal devicethat has accessed the wireless communication network.

The term “terminal device” refers to any end device that can access awireless communication network and receive services therefrom. By way ofexample and not limitation, the terminal device refers to a mobileterminal, user equipment (UE), or other suitable devices. The UE may be,for example, a Subscriber Station (SS), a Portable Subscriber Station, aMobile Station (MS), or an Access Terminal (AT). The terminal device mayinclude, but not limited to, portable computers, image capture terminaldevices such as digital cameras, gaming terminal devices, music storageand playback appliances, a mobile phone, a cellular phone, a smartphone, voice over IP (VoIP) phones, wireless local loop phones, atablet, a wearable device, a personal digital assistant (PDA), portablecomputers, desktop computer, image capture terminal devices such asdigital cameras, gaming terminal devices, music storage and playbackappliances, wearable terminal devices, vehicle-mounted wireless terminaldevices, wireless endpoints, mobile stations, laptop-embedded equipment(LEE), laptop-mounted equipment (LME), USB dongles, smart devices,wireless customer-premises equipment (CPE) and the like. In thefollowing description, the terms “terminal device”, “terminal”, “userequipment” and “UE” may be used interchangeably. As one example, aterminal device may represent a UE configured for communication inaccordance with one or more communication standards promulgated by the3rd Generation Partnership Project (3GPP), such as 3GPP's GSM, UMTS,LTE, and/or 5G standards. As used herein, a “user equipment” or “UE” maynot necessarily have a “user” in the sense of a human user who owns andor operates the relevant device. In some embodiments, a terminal devicemay be configured to transmit and/or receive information without directhuman interaction. For instance, a terminal device may be designed totransmit information to a network on a predetermined schedule, whentriggered by an internal or external event, or in response to requestsfrom the wireless communication network. Instead, a UE may represent adevice that is intended for sale to, or operation by, a human user butthat may not initially be associated with a specific human user.

The terminal device may support device-to-device (D2D) communication,for example by implementing a 3GPP standard for sidelink communication,and may in this case be referred to as a D2D communication device.

As yet another example, in an Internet of Things (IOT) scenario, aterminal device may represent a machine or other device that performsmonitoring and/or measurements, and transmits the results of suchmonitoring and/or measurements to another terminal device and/or networkequipment. The terminal device may in this case be a machine-to-machine(M2M) device, which may in a 3GPP context be referred to as amachine-type communication (MTC) device. As one particular example, theterminal device may be a UE implementing the 3GPP narrow band internetof things (NB-IoT) standard. Particular examples of such machines ordevices are sensors, metering devices such as power meters, industrialmachinery, or home or personal appliances, for example refrigerators,televisions, personal wearables such as watches etc. In other scenarios,a terminal device may represent a vehicle or other equipment that iscapable of monitoring and/or reporting on its operational status orother functions associated with its operation.

As used herein, a downlink, DL transmission refers to a transmissionfrom the network device to a terminal device, and an uplink, ULtransmission refers to a transmission in an opposite direction.

References in the specification to “one embodiment,” “an embodiment,”“an example embodiment,” and the like indicate that the embodimentdescribed may include a particular feature, structure, orcharacteristic, but it is not necessary that every embodiment includesthe particular feature, structure, or characteristic. Moreover, suchphrases are not necessarily referring to the same embodiment. Further,when a particular feature, structure, or characteristic is described inconnection with an embodiment, it is submitted that it is within theknowledge of one skilled in the art to affect such feature, structure,or characteristic in connection with other embodiments whether or notexplicitly described.

It shall be understood that although the terms “first” and “second” etc.may be used herein to describe various elements, these elements shouldnot be Limited by these terms. These terms are only used to distinguishone element from another. For example, a first element could be termed asecond element, and similarly, a second element could be termed a firstelement, without departing from the scope of example embodiments. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed terms.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be liming of exampleembodiments. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises”, “comprising”, “has”, “having”, “includes” and/or“including”, when used herein, specify the presence of stated features,elements, and/or components etc., but do not preclude the presence oraddition of one or more other features, elements, components and/orcombinations thereof.

In the following description and claims, unless defined otherwise, alltechnical and scientific terms used herein have the same meaning ascommonly understood by one of ordinary skills in the art to which thisdisclosure belongs.

Multiple numerology operation in the NR system may comprise two aspects:

Case scenario 1: Different numerologies can be configured for differentcarriers. For instance, small subcarrier spacing (SCS) may be appliedfor carriers of low frequency and large SCS may be applied for carrierof high frequency. For one given carrier frequency range, there may bemore than one candidate numerology so that the network can select whichnumerology is to be applied for one carrier within the range consideringthe traffic quality of service (QoS) requirement and/or networkdimension requirement. For one instance, if the network coverage is morea priority than transmission delay in air interface, the network canconfigure a small SCS for one carrier at low frequencies. For anotherinstance, if radio access network (RAN) transmission delay is more apriority than the network coverage, the network can configure a largeSCS for the carrier to get a short TTI duration. In addition, thebandwidth and transmission time interval (TTI) may be different fordifferent carriers.

Case scenario 2: There can be multiple Bandwidth Parts (BWPs) configuredin one carrier and one LE can be configured with one or multiple BWPs.Different BWPs may be configured with different numerologies to meetdifferent QoS requirements. FIG. 2 shows an example of multiple BWPconfigurations in one carrier. As shown in FIG. 2, there are two BWPconfigurations in one NR carrier, BWP1 with numerology 1 and BWP2 withnumerology 2. For the BWP1 with numerology 1, TTI of numerology 1 isused, and for the BWP2 with numerology 2, TTI (transmission timeinterval) of numerology 2 is used. It is noted that the BWPconfigurations as shown in FIG. 2 are only exemplary and may bedifferent in other embodiments.

The timing adjustment indication is specified in 3GPP TS 36.331-e20, thedisclosure of which is incorporated by reference herein in its entirety.The timing adjustment indication indicates an initial N_(TA) used for aTAG (timing advance group) The TA command for a TAG indicates the changeof the uplink timing relative to the current uplink timing for the TAGas multiples of 1671. The start timing of the random access preamble isspecified in 3GPP TS 36.211, the disclosure of which is incorporated byreference herein in its entirety.

In the case of random access response (RAR), an 11-bit timing advancecommand T_(A) for a TAG indicates N_(TA) values by index values ofT_(A)=0, 1, 2, . . . , 256 if the UE is configured with a Secondary CellGroup (SCG), and T_(A)−0, 1, 2, . . . , 1282 otherwise, wherein anamount of the time alignment for the TAG is given by N_(TA)=T_(A)×16.

In other cases, a 6-bit timing advance command (see 3GPP TS 36.321-e20,the disclosure of which is incorporated by reference herein in itsentirety), T_(A), for a TAG indicates adjustment of the current N_(TA)value, N_(TA,old), to the new N_(TA) value. N_(TA,new), by index valuesof TA=0, 1, 2, . . . , 63, where N_(TA,new)=N_(TA,old)+(T_(A)−31)×16.Herein, adjustment of N_(TA) value by a positive or a negative amountindicates advancing or delaying the uplink transmission timing for theTAG by a given amount respectively. For LTE, the granularity is around0.5208 us.

In 3GPP TS 36.321-e20, the Timing Advance Command MAC control element(CE) is identified by MAC Protocol Data Unit (PDU) subheader with LCIDas specified in table 6.2.1-1 in 3GPP TS 36.321-e20.

The liming Advance Command MAC control element has a fixed size andconsists of a single octet defined as in FIG. 3 which is copy of FIG.6.1.3.5-1 of 3GPP TS 36.321-e20. The Timing Advance Command MAC controlelement comprises:

-   -   TAG Identity (TAG Id): This field indicates the TAG Identity of        the addressed TAG. The TAG containing the SpCell has the TAG        Identity 0. The length of the field is 2 bits;    -   Timing Advance Command: This field indicates the index value TA        (0, 1, 2 . . . 63) used to control the amount of timing        adjustment that MAC entity has to apply. The length of the field        is 6 bits.

It is noted that LTE only supports a single numerology operation and afixed TA adjustment configuration.

When a UE is configured with multiple numerologies, the SCS and CyclicPrefix (CP) length of different numerology may be different. This meansthat the allowed timing error for uplink transmission is different whenthe uplink transmission changes from one numerology to anothernumerology.

If the same TA granularity (i.e. 0.52 us) as LTE is applied in awireless system supporting multiple numerology operation, it may resultin an inaccuracy problem tor a numerology with shorter CP length.Accordingly, the fixed TA adjustment configuration used by LTE becomesunsuitable for a wireless system such as NR supporting multiplenumerology operation. For example, the fixed TA adjustment configurationis unsuitable when higher SCS and lower CP length are applied.

Another issue is that the wireless system supporting multiple numerologyoperation is required to introduce a unified TA framework so that thefrequent change of numerology doesn't affect stability of the timingadvance management. In other words, the UE should not update the TAsetting too often to simplify its management efforts.

The present disclosure proposes a solution for TA adjustment in awireless system supporting multiple numerology operation, such as a NRsystem. It may overcome at least one of the drawbacks mentioned above,or it may not overcome any one of the drawbacks mentioned above. It isnoted that though the embodiments are mainly described in the context ofthe NR system, they are not limited to this but can be applied to anysuitable wireless system. In addition, it is noted that the embodimentscan be applied to unlicensed channel operation and/or licensed channeloperation.

Now some exemplary embodiments of the present disclosure will bedescribed below with reference to the figures.

FIG. 1 depicts a schematic system, in which some embodiments of thepresent disclosure can be implemented. While this and other embodimentsbelow are primarily discussed in the context of a NR system, it will berecognized by those of ordinary skill that the disclosure is not solimited. In fact, the various aspects of this disclosure are useful inany wireless network/system that can benefit tram the embodiments as isdescribed herein, such as TDMA, TD-SCDMA, OFDM A, SC-FDMA and otherwireless networks supporting multiple numerology operation. The terms“network” and “system” are often used interchangeably. A TDMA networkmay implement a radio technology such as Global System for MobileCommunications (GSM). An OFDMA network may implement a radio technologysuch as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20. Flash-OFDMA, Ad-hoc network,wireless sensor network, etc.

As shown in FIG. 1, the wireless system 100 comprises a network device110 such as a cellular base station, for example a gNB in NR. Thenetwork device 110 may refer to a function element on the network sideas compared to a terminal device or UE. For example, the network device110 may comprise an eNB, a Home eNode B, a femto Base Station, a picoBS, gNB or any other node capable to serve terminal devices 104-10 n inthe system 100. It is well known that a cellular radio system maycomprise a network of radio cells each served by a transmitting station,known as a cell site or base transceiver station. The radio networkprovides wireless communications service for a plurality of transceivers(in most cases mobile). The network of network devices working incollaboration allows for wireless service which is greater than theradio coverage provided by a single network device. The individualnetwork device may be connected by another network (in many cases awired network, not shown), which includes additional controllers forresource management and in some cases access to other network systems(such as the Internet) or metropolitan area networks (MANs). The circle130 schematically indicates a coverage range of the network device 110.

As shown in FIG. 1, the system 100 may comprise one or more UEs orterminal devices 104-10 n, each of which may operably communicate withthe network device 110 such as a cellular base station through awireless link, such as link 120 and 124. The terms “terminal device” and“UE” are often used interchangeably. The terminal devices 104-10 n canbe fixed or moveable. Terminal devices 104-10 n may include, but notlimited to, cellular telephones, smart phones, and computers, whetherdesktop, laptop, or otherwise, as well as mobile devices or terminalssuch as cellular network UEs, machine type communication devices,handheld computers, personal digital assistants (PDAs), wirelesssensors, wearable devices, video cameras, set-top boxes, personal mediadevices, or any combinations of the foregoing, which may be providedwith wireless communication functionality and run with any kind ofoperating system including, but not limited to, Windows. Linux, UNIX,Android, iOS and their variants.

In addition, though only one network device 110 is shown in FIG. 1,there may be two or more network devices such that some terminal devicesare within the coverage range of first network device, some terminaldevices are within the coverage range of second network device, and someterminal devices are at the border of the coverage ranges of two or morenetwork devices, and so on. In the latter case, the terminal devices mayreceive signals from each of the two or more network devices.

FIG. 4 is a flow chart depicting a method 400 for TA adjustmentaccording to an embodiment of the present disclosure, which may beperformed at an apparatus such as the network device 110 of FIG. 1. Assuch, the network device 110 may provide means for accomplishing variousparts of the method 400 as well as means for accomplishing otherprocesses in conjunction with other components.

As shown in FIG. 4, the method 400 may start at block 402 where thenetwork device 110 determines a TA value for a terminal device, whereindifferent numerologies are configured for at least two carriers and/orat least two bandwidth parts (BWPs) in one carrier, wherein the at leasttwo carriers and/or the at least two BWPs serve the terminal device andthe terminal device supports at least one numerology. Die network device110 may determine the TA value for the terminal device by using anysuitable existing or future developed technology. For example, thenetwork device 110 may determine the TA value for the terminal devicefrom an uplink signal received from the terminal device.

At block 404, the network device 110 determines a TA granularity orrange for the terminal device. For example, the network device 110 maydetermine the TA granularity or range for the terminal device based on apredefined rule which is known by both the terminal device and thenetwork device 110. As an example, the network device 110 may bepreconfigured with a plurality of TA granularities or ranges each ofwhich corresponds to a range of the subcarrier spacing, CP length orcarrier frequency, then the network device 110 can determine the TAgranularity according to one or multiple of subcarrier spacing, CPlength and carrier frequency, and optionally send the TA granularity orrange to the terminal device. As another example, a specific terminaldevice (for example, a fixed terminal device or a terminal device with ahigher priority, etc) may have a predefined table which defines thecorrespondence between at least one of radio parameters (subcarrierspacing, cyclic prefix (CP) length and carrier frequency) and TAgranularity or range, then the network device 110 may determine the TAgranularity or range for the terminal device by looking up the table.

In an embodiment, the network device 110 may determine the TAgranularity or range by at least one of a cyclic prefix (CP) length, anumerology and a carrier frequency used by the terminal device, whereinthere is a correspondence between CP length and TA granularity or range,a correspondence between numerology and TA granularity or range, and acorrespondence between carrier frequency and TA granularity or range,wherein the correspondences are preconfigured in the network deviceand/or the correspondences are preconfigured in the terminal device orsignaled to the terminal device.

Table 1 shows a correspondence between CP length and TA granularity orrange. Both the network device 110 and the terminal device may determinethe TA granularity or range by looking up the table 1 according to theCP length of the operating numerology. A short CP length is mapped to asmall TA granularity or range for timing adjustment to maintain timingerrors within a given CP range. In the case of multiple numerologiesconfigured for one carrier or for carrier aggregation (CA), the shortestCP may be used as reference numerology. Then the reference numerology isused as entry to look up the table. Alternatively, the network device110 indicates which CP should be used for TA granularity selection. ItIs noted that Table 1 is only exemplary and may be different in otherembodiments.

TABLE 1 CP length TA granularity or range CP length >= y Large timegranularity (e.g. 0.52 us) or large time range y > CP length >= x Mediumtime granularity (e.g. 0.26 us) or medium time range CP length < x Smalltime granularity (<0.26 us) or small time range

Table 2 shows a correspondence between currier frequency and TAgranularity or range. Both the network device 110 and the terminaldevice may determine the TA granularity or range by looking up the table2 according to the operating carrier frequency. For example, a carrierwith high frequency can use a numerology associated with a large SCS,correspondingly a small CP length is accompanied, so a carrier of highfrequency may map to a small TA granularity. In the case of CA, thehighest carrier frequency may determine the TA selection. Alternatively,the network device 110 indicates which numerology/carrier frequencyshould be used for TA granularity selection. It is noted that Table 2 isonly exemplary and may be different in other embodiments.

TABLE 2 Carrier frequency range TA granularity or range Freq < 6 GHzLarge time granularity (e.g. 0.52 us) or large time range 30 GHz >=Freq > 6 GHz Medium lime granularity (e.g. 0.26 us) or medium time rangeFreq > 30 GHz Small time granularity (<0.26 us) or small time range

Table 3 shows a correspondence between numerology (such as SCS and BWP)and TA granularity or range. Both the network device 110 and theterminal device may determine the TA granularity or range by looking upthe table according to the operating numerology. For example, the higherSCS of a numerology, the smaller CP length of the numerology tends touse. Based on this mapping relationship, the correspondence of table canbe created. In the case of multiple numerologies configured for onecarrier or for CA, the widest subcarrier spacing may be used.Alternatively, the network device 110 indicates which subcarrier spacingshould be used for TA granularity selection. It is noted that Table 3 isonly exemplary and may be different in other embodiments.

TABLE 3 Numerology TA granularity or range SCS = 15 kHz Large timegranularity (e.g. 0.52 us) or large time range SCS = 30 kHz Medium timegranularity (e.g. 0.26 us) or medium time range SCS > 30 kHz Small timegranularity (<0.26 us) or small time range

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, the network device 110 determines the TA granularity orrange based on the reference numerology and the reference numerology isa numerology with the shortest CP length or widest sub-carrier spacing.For example, for a NR UE supporting multiple numerologies, eachnumerology may be mapped with a separate BWP, therefore, a carrier maycomprise multiple BWPs and each is associated with a distinctnumerology, or the numerology is configured per carrier. For the formercase, a reference numerology may be defined, and based on which the UEcan derive the TA granularity or range by looking up a table such asTable 3. The reference numerology can be determined among allnumerologies irrespective of their associated BWPs are active orinactive, or consider only active numerologies. The referencenumerology/CP can be the one with shortest CP, which requires the finestTA granularities. For the latter case where each carrier is configuredwith a different numerology, the UE determines the TA granularity foreach carrier separately or in a similar way as tor the multiplenumerologies on the same carrier (BWP above) (i.e. on TA granularitybased on a reference numerology).

In on embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell. For example, different referencenumerology/CP may be defined separately for the UE under RRC_IDLE andRRC_CONNECTED states. The numerology assigned for UEs under RRC_IDLEcould be same in the cell. For example, UEs may obtain their initial TAvalues via RAR message, based on the reference numerology/CP. When UEsswitch up to RRC_CONNECTED state, the TA value can be updated wheneverthe reference numerology changes.

In an embodiment, after determining the TA granularity or range, thenetwork device 110 sends a message containing the TA granularity orrange to the terminal device. For example, the message can be senttogether with a TA command or any other suitable message. Then theterminal device can determine the TA granularity or range from themessage.

Turn to FIG. 4, at block 406, the network device 110 generates a TAcommand based on the TA value and the TA granularity or range. Forexample, TA command can comprise a field indicating an index valueassociated with the TA granularity or range used to control the amountof timing adjustment. In thus case, the network device 110 may generatea TA command comprising the index value. In another embodiment where theTA command comprises the index value and TA granularity or range, thenetwork device 110 may generate a TA command comprising the index valueand TA granularity or range. It is noted that the TA command maycomprise any other suitable fields such as TAG.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation. For example, the format of TA command in NR may be the sameas ernes used in LTE, i.e. 11-bit TA command in RAR, and 6-bit TAcommand in MAC CE. The bits of the field of TA command may be not fullyoccupied in some cases. The maintenance of TA is simple in this case,since all numerologies/CP lengths use the same format as ones used in awireless network supporting single numerology operation such as LTE.

In another embodiment, the format of the TA command is different fromthe format of the TA command used in a wireless network supportingsingle numerology operation such as LTE. Different format Ls designed tocarry the TA value for different TA granularity or range requirements.For small time granularity, more bits are needed to ensure a rangesufficient for time adjustment.

FIG. 5 shows four formats for TA command signaled in MAC CE. For format0, 1, 2, a predefined mapping between the TA granularity or range andthe MAC CE format can be stored in both the UE and the network device110. Table 4 shows one mapping example between the TA granularity orrange and the MAC CE format.

TABLE 4 Format TA granularity or range Format 0 Large time granularity(e.g. 0.52 us) or large time range Format 1 Medium time granularity(e.g. 0.26 us) or medium time range Format 2 Small time granularity(<0.26 us) or small time rangeFormat 3 comprises an indicator of the TA granularity or range. In thiscase, the network device 110 may indicate the TA granularity or range inthe MAC CF, together with the TA to the terminal device such that theterminal device can directly determine the TA granularity or range fromthe received TA command with format 3. It is noted that the aboveformats are only exemplary and may be different in other embodiments. Inaddition, any other suitable format of the TA command may be designedfor other messages such as RAR.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change as shown in above formats 0-3. It isnoted that the above formats are only exemplary and may be different inother embodiments.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, and the network device 110 candetermine the format of the TA command based on the TA granularity orrange. For example, the network device 110 can determine the TAgranularity or range for the terminal device as described above, thenthe network device 110 can determine the format of the TA command basedon the TA granularity or range, for example by looking up a table suchas Table 4 containing the correspondence between the format of the TAcommand and the TA granularity or range.

Turning to FIG. 4, at block 408, the network device 110 sends the TAcommand to the terminal device. For example, the network device 110 maysend the TA command in RAR or MAC CE to the terminal device.Alternatively, the network device 110 may send the TA command in othersuitable messages to the terminal device.

In an embodiment, the TA command is sent together with uplink grant or amedium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused few the UL grant or the numerology of PUSCH scheduled by the ULgrant. For example, the TA granularity or range is defined by thenumerology used in the uplink grant transmitted together with the TAcommand. This embodiment may be suitable for an case where the TAcommand is transmitted as a Layer 1 indication by the DO (DownlinkControl Information). Here, a DCI for uplink grant could then contain afield for TA command, where the numerology used for this UI, grant givesthe granularity for the TA command. For example, with a SCS of 15 kHz inthe UL grant, then the TA granularity is 0.52 microseconds. If the SCSis 30 kHz, then the TA granularity is 0.26 microseconds. This embodimentmay be suitable for an case where the TA command is transmitted as a MACcommand and the MAC command is associated With a specific UL grant.

FIG. 6a is flow chart depicting a method 600′ for TA adjustmentaccording to an embodiment of the present disclosure, which may beperformed at an apparatus such as terminal devices 104-10 n of FIG. 1.As such, terminal device 104-10 n may provide means for accomplishingvarious parts of the method 600′ as well as means for accomplishingother processes in conjunction with other components. For some partswhich have been described in the above embodiments, detailed descriptionthereof is omitted here for brevity.

As shown in FIG. 6a , the method 600′ may start at block 602′ whereterminal device 104 receives a TA command from a network device.

In an embodiment, different numerologies are configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies. The TA commandmay be included in any suitable messages such as RAR or MAC CE.Alternatively, the TA command may be included in other suitablemessages.

At block 604′, the terminal device 104 determines a TA granularity. Forexample, the terminal device 104 may determine the TA granularity forthe terminal device based on a predefined rule which is known by boththe terminal device 104 and the network device 110. As an example, aspecific terminal device (for example, a fixed terminal device or aterminal device with a higher priority, etc) may have a predefined TAgranularity, then the terminal device 104 may determine the TAgranularity for the terminal device by the predefined TA granularity.

In an embodiment, the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device. There is acorrespondence between numerology and TA granularity.

In an embodiment, the terminal device 104 may determine the TAgranularity by at least one of a cyclic prefix (CP) length, a numerologyand a carrier frequency-used by the terminal device, wherein there is acorrespondence between CP length and TA granularity, a correspondencebetween numerology and TA granularity, and a correspondence betweencarrier frequency and TA granularity, wherein the correspondences arepreconfigured in the network device and/or the correspondences arepreconfigured in the terminal device or signaled to the terminal device.The determining procedure in the terminal device 104 is similar to thatin the network device 110 which has been described above with referenceto Tables 1-3, therefore detailed description about it is omitted herefor brevity.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, the terminal device 104 determines the TA granularity basedon the reference numerology and the reference numerology is a numerologywith the shortest CP length. The determining procedure in the terminaldevice 104 is similar to that in the network device 110 which has beendescribed above, therefore detailed description about it is omitted herefor brevity.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell. For example, different referencenumerology/CP may be defined separately for the UE under RRC_IDLE andRRC_CONNECTED states. The numerology assigned for UEs under RRC_IDLEcould be same in the cell.

For example, UEs may obtain their initial TA values via RAR message,based on the reference numerology/CP. When UEs switch up toRRC_CONNECTED state, the TA value can be updated whenever the referencenumerology changes.

In an embodiment, the terminal device 104 receives a message containingthe TA granularity from the network device. For example, the message canbe received together with a TA command or any other suitable message. Inthis case, the terminal device 104 determines the TA granularity fromthe received TA granularity.

Turn to FIG. 6a ′, at block 606′, the terminal device 104 determines aTA value based at least partly on the TA command and the TA granularity.For example, when the TA granularity is not changed, the terminal device104 may determine the TA value by using similar approach as LTE.

In another embodiment, the terminal device 104 may determine the TAvalue by updating a previous TA value considering the difference ofbetween an old TA granularity and a new TA granularity; calculating a TAcompensation based on the new TA command and the new TA granularity; anddetermining the TA value based on the updated previous TA value and theTA compensation. For example, the terminal device 104 updates thecurrent N_(TA) value, N_(TA,old), and the new N_(TA) value. N_(TA,new)together. N_(TA,old) is updated since h was calculated with the old TAgranularity. As a base, it is recalculated with the new TA granularityand the old TA value. As a further step, N_(TA,new) is adjusted bysumming the updated N_(TA,old) and the TA compensation. The TAcompensation is calculated with the recent received TA index and the newTA granularity.

FIG. 6b is flow chart depicting a method 600 for TA adjustment accordingto an embodiment of the present disclosure, which may be performed at anapparatus such as terminal devices 104-10 n of FIG. 1. As such, terminaldevice 104-10 n may provide means for accomplishing various parts of themethod 600 as well as means for accomplishing other processes inconjunction with other components. For some parts which have beendescribed in the above embodiments, detailed description thereof isomitted here for brevity.

As shown in FIG. 6b , the method 600 may start at block 602 whereterminal device 104 receives a TA command from a network device, whereindifferent numerologies are configured for at least two earners and/or atleast two bandwidth parts (BWPs) in one carrier as described above,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology. The TA command may be included in any suitable messages suchas RAR or MAC CE. Alternatively, the TA command may be included in othersuitable messages.

At block 604, the terminal device 104 determines a TA granularity orrange. For example, the terminal device 104 may determine the TAgranularity or range for the terminal device based on a predefined rulewhich is known by both the terminal device 104 and the network device110. As an example, a specific terminal device (for example, a fixedterminal device or a terminal device with a higher priority, etc) mayhave a predefined TA granularity or range, then the terminal device 104may determine the TA granularity or range for the terminal device by thepredefined TA granularity or range.

In an embodiment, the terminal device 104 may determine the TAgranularity or range by at least one of a cyclic prefix (CP) length, anumerology and a carrier frequency used by the terminal device, whereinthere is a correspondence between CP length and TA granularity or range,a correspondence between numerology and TA granularity or range, and acorrespondence between carrier frequency and TA granularity or range,wherein the correspondences are preconfigured in the network deviceand/or the correspondences are preconfigured in the terminal device orsignaled to the terminal device. The determining procedure in theterminal device 104 is similar to that in the network device 110 whichhas been described above with reference to Tables 1-3, thereforedetailed description about it is omitted here for brevity.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, the terminal device 104 determines the TA granularity orrange based on the reference numerology and the reference numerology isa numerology with the shortest CP length. The determining procedure inthe terminal device 104 is similar to that in the network device 110which has been described above, therefore detailed description about itis omitted here for brevity.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell. For example, different referencenumerology/CP may be defined separately for the UE under RRC_IDLE andRRC_CONNECTED states. The numerology assigned for UEs under RRC_IDLEcould be same in the cell. For example, UEs may obtain their initial TAvalues via RAR message, based on the reference numerology CP. When UEsswitch up to RRC_CONNECTED state, the TA value can be updated wheneverthe reference numerology changes.

In an embodiment, the terminal device 104 receives a message containingthe TA granularity or range from the network device. For example, themessage can be received together with a TA command or any other suitablemessage. In this case, the terminal device 104 determines the TAgranularity or range from the received TA granularity or range.

Turn to FIG. 6, at block 606, the terminal device 104 determines a TAvalue based on one or more of the TA command and the TA granularity orrange. For example, when the TA granularity or range is not changed, theterminal device 104 may determine the TA value by using similar approachas LTE.

In another embodiment, the terminal device 104 may determine the TAvalue by updating a previous TA value considering the difference ofbetween an old TA granularity or range and a new TA granularity orrange; calculating a TA compensation based on the new TA command and thenew TA granularity or range; and determining the TA value based on theupdated previous TA value and the TA compensation. For example, theterminal device 104 updates the current N_(TA) value, N_(TA,old), andthe new N_(TA) value, N_(TA,new) together. N_(TA,old) is updated sinceit was calculated with the old TA granularity or range. As a base, it isrecalculated with the new TA granularity and the old TA value. As afurther step, N_(TA,new) is adjusted by summing the updated N_(TA,old)and the TA compensation. The TA compensation is calculated with therecent received TA index and the new TA granularity.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation. For example, the format of TA command in NR may be the sameas ones used in LTE, i.e, 11-bit TA command in RAR, and 6-bit TA commandin MAC CE. The bits of the field of TA command may be not fully occupiedin sane cases. The maintenance of TA is simple in this case, since allnumerologies/CP lengths use the same format as ones used in a wirelessnetwork supporting single numerology operation such as LTE.

In another embodiment, the format of the TA command is different fromthe format of the TA command used in a wireless network supportingsingle numerology operation. Different format is designed to carry theTA value for different TA granularity requirements. For small timegranularity, more bits are needed to ensure an enough range for timeadjustment. In an embodiment, the format of the TA command changes inrelation to the TA command field length change. The formats have beendescribed above, therefore detailed description about them is omittedhere for brevity.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, and the terminal device 104 candetermine the format of the TA command based on the TA granularity orrange. For example, the terminal device 104 can determine the TAgranularity or range as described above, then the terminal device 104can determine the format of the TA command based on the TA granularityor range, for example by looking up a table such as Table 4 containingthe correspondence between the format of the TA command and the TAgranularity or range.

In an embodiment, the terminal device 104 receives the TA commandtogether with uplink grant or a medium access control (MAC) commandassociated with uplink grant, wherein the TA granularity or range isdetermined based on a numerology used for the UI, grant or thenumerology of PUSCH scheduled by the UT, grant. For example, the TAgranularity or range is defined by the numerology used in the uplinkgrant transmitted together with the TA command. This embodiment would beuseful if the TA command is transmitted as a Layer 1 indication by theDO (Downlink Control Information). Here, a DCI for uplink grant couldthen contain a field for TA command, where the numerology used for thisUL grant gives the granularity for the TA command. For example, with aSCS of 15 kHz in the UL grant, then the TA granularity is 0.52microseconds. If the SCS is 30 kHz, then the TA granularity is 0.26microseconds. This embodiment may be suitable for an case where the TAcommand is transmitted as a MAC command and the MAC command isassociated with a specific UL grant.

FIG. 7 is a flowchart illustrating methods for TA adjustment on both anetwork device's side and a terminal device's side according to anembodiment of the disclosure. For some parts which have been describedin the above embodiments, detailed description thereof is omitted herefor brevity.

At block 702, the network device 110 determines a TA value for aterminal device 104, wherein different numerologies are configured forat least two carriers and/or at least two bandwidth parts (BWPs) in onecarrier, wherein the at least two carriers and/or the at least two BWPsserve the terminal device and the terminal device supports at least onenumerology.

At block 704, the network device 110 determines a TA granularity orrange for the terminal device 104.

In an embodiment, the TA granularity or range is determined by at leastone of a cyclic prefix (CP) length, a numerology and a carrier frequencyused by the terminal device, wherein there is a correspondence betweenCP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

Optionally, at block 706, the network device 110 sends a messagecontaining the TA granularity or range to the terminal device 104.

Optionally, at block 708, the terminal device 104 receives a messagecontaining the TA granularity or range.

At block 710, the network device 110 generates a TA command based on theTA value and the TA granularity or range.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation. In another embodiment, the format of the TA command isdifferent from a format of the TA command used in a wireless networksupporting single numerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, when there is a correspondence between the format ofthe TA command and the TA granularity or range, the network device 110determines the format of the TA command based on the TA granularity orrange at block 710.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

At block 712, the network device 110 sends the TA command to theterminal device 104. In an embodiment, the TA command is sent togetherwith uplink grant or a medium access control (MAC) command associatedwith uplink grant, wherein the TA granularity or range is determinedbased on a numerology used for the UL grant or the numerology of PUSCHscheduled by the UL grant.

At block 714, the terminal device 104 receives a TA command from thenetwork device 110. In an embodiment, the TA command is receivedtogether with uplink grant or a medium access control (MAC) commandassociated with uplink grant, wherein the TA granularity or range isdetermined based on a numerology used for the UL grant or the numerologyof PUSCH scheduled by the UL grant.

At block 716, the terminal device 104 determines a TA granularity orrange.

In an embodiment the TA granularity or range is determined by one ormore of a cyclic prefix (CP) length, a numerology and a carrierfrequency used by the terminal device, wherein there is a correspondencebetween CP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

At block 718, the terminal device 104 determines a TA value based on atleast partly on the TA command and the TA granularity or range. In anembodiment the terminal device 104 determines a TA granularity or rangeby updating a previous TA value considering the difference of between anold TA granularity or range and a new TA granularity or range;calculating a TA compensation based on the new TA command and the new TAgranularity or range; and determining the TA value based on the updatedprevious TA value and the TA compensation.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the terminal device 104determines the format of the TA command based on the TA granularity orrange.

FIG. 8 depicts a network device 800 capable of implementing the methodfor TA adjustment as described above. As shown in FIG. 8, the networkdevice 800 comprises a processing device 804, a memory 805, and a radiomodem subsystem 801 in operative communication with the processor 804.The radio modem subsystem 801 comprises at least one transmitter 802 andat least one receiver 803. While only one processor is illustrated inFIG. 8, the processing device 804 may comprises a plurality ofprocessors or multi-core processor(s). Additionally, the processingdevice 804 may also comprise cache to facilitate processing operations.

Computer-executable instructions can be loaded in the memory 805 and,when executed by the processing device 804, cause the network device 800to implement the above-described methods for TA adjustment. Inparticular, the computer-executable instructions can cause the networkdevice 800 to determine a TA value for a terminal device; determine a TAgranularity or range for the terminal device; generate a TA commandbased at least partly on the TA value and the TA granularity or range;and said the TA command to the terminal device.

In an embodiment, different numerologies ore configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device. There is acorrespondence between numerology and TA granularity.

In an embodiment, different numerologies are configured for at least twocarriers and/or at least two bandwidth parts, BWPs, in one carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

In an embodiment, the TA granularity or range is determined by at leastone of a cyclic prefix (CP) length, a numerology and a carrier frequencyused by the terminal device, wherein there is a correspondence betweenCP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the computer-executable instructions can cause thenetwork device 800 to send a message containing the TA granularity orrange to the terminal device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the computer-executableinstructions can cause the network device 800 to determine the format ofthe TA command based on the TA granularity or range.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is sent together with uplink grant or amedium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused for the UL grant or the numerology of PUSCH scheduled by the ULgrant.

FIG. 9 depicts a terminal device 900 capable of implementing the methodsfor TA adjustment as described above. As shown in FIG. 9, the terminaldevice 900 comprises a processing device 904, a memory 905, and a radiomodem subsystem 901 in operative communication with the processor 904.The radio modem subsystem 901 comprises at least one transmitter 902 andat least one receiver 903. While only one processor is illustrated inFIG. 9, the processing device 904 may comprises a plurality ofprocessors or multi-core processor(s). Additionally, the processingdevice 904 may also comprise cache to facilitate processing operations.

Computer-executable instructions can be loaded in the memory 905 and,when executed by the processing device 904, cause the terminal device900 to implement the above-described methods for TA adjustment. Inparticular, the computer-executable instructions can cause the terminaldevice 900 to receive a TA command from a network device; determine a TAgranularity or range; and determine a TA value based on at least partlyon the TA command and the TA granularity or range.

In on embodiment, different numerologies are configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device. There is acorrespondence between numerology and TA granularity.

In an embodiment, different numerologies are configured for at least twocarriers and/or at least two bandwidth parts, BWPs, in ore carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

In an embodiment, the TA granularity or range is determined by one ormore of a cyclic prefix (CP) length, a numerology and a carrierfrequency used by the terminal device, wherein there is a correspondencebetween CP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the computer-executable instructions can cause theterminal device 900 to receive a message containing the TA granularityor range from the network device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

In an embodiment, the computer-executable instructions can cause theterminal device 900 to update a previous TA value considering thedifference of between an old TA granularity or range and a new TAgranularity or range; calculate a TA compensation based on the new TAcommand and the new TA granularity or range; and determine the TA valuebased on the updated TA value and the TA compensation.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the method further comprisesdetermining the format of the TA command based on the TA granularity orrange.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is received together with uplink grantor a medium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused for the UL grant or the numerology of PUSCH scheduled by the ULgrant.

According to an aspect of the disclosure it is provided a computerprogram product comprising at least one non-transitory computer-readablestorage medium having computer-executable program instructions storedtherein, the computer-executable Instructions being configured to, whenbeing executed, cause a network device to operate as described above.

According to an aspect of the disclosure it is provided a computerprogram product comprising at least one non-transitory computer-readablestorage medium having computer-executable program instructions storedtherein, the computer-executable instructions being configured to, whenbeing executed, cause a terminal device to operate as described above.

FIG. 10 depicts a network device 1000 capable of implementing the methodfor TA adjustment as described above. As shown in FIG. 10, the networkdevice 1000 comprises a first determination module 1002 for determininga TA value for a terminal device; a second determination module 1004 fordetermining a TA granularity or range for the terminal device; ageneration module 1006 for generating a TA command based at least partlyon the TA value and the TA granularity or range; and a transmissionmodule 1008 for sending the TA command to the terminal device.

In an embodiment, different numerologies are configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device. There is acorrespondence between numerology and TA granularity.

In an embodiment, different numerologies are configured for at least twocarriers and/or at least two bandwidth parts, BWPs, in one carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

In an embodiment, the TA granularity or range is determined by at leastone of a cyclic prefix (CP) length, a numerology and a carrier frequencyused by the terminal device, wherein there is a correspondence betweenCP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the transmission module 1008 is configured to send amessage containing the TA granularity or range to the terminal device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle stale is same in a cell.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the network device 1000 furthercomprises a third determination module (not shown) for determining theformat of the TA command based on the TA granularity or range.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is sent together with uplink grant or amedium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused for the UL grant or the numerology of PUSCH scheduled by the ULgrant.

FIG. 11 depicts a terminal device 1100 capable of implementing themethods Tor TA adjustment as described above. As shown in FIG. 11, theterminal device 1100 comprises a reception module 1102 for receiving aTA command from a network device; a first determination module 1104 fordetermining a TA granularity or range; and a second determination module1106 for determining a TA value based at least partly on the TA commandand the TA granularity or range.

In an embodiment, different numerologies are configured for at least twocarriers, wherein the at least two carriers serve the terminal deviceand the terminal device supports multiple numerologies.

In an embodiment, the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device. There is acorrespondence between numerology and TA granularity.

In an embodiment, different numerologies are configured for at least twocarriers and/or at least two bandwidth parts, BWPs, in one carrier,wherein the at least two carriers and/or the at least two BWPs serve theterminal device and the terminal device supports at least onenumerology.

In an embodiment, the TA granularity or range is determined by one ormore of a cyclic prefix (CP) length, a numerology and a carrierfrequency used by the terminal device, wherein there is a correspondencebetween CP length and TA granularity or range, a correspondence betweennumerology and TA granularity or range, and a correspondence betweencarrier frequency and TA granularity or range, wherein thecorrespondences are preconfigured in the network device and/or thecorrespondences are preconfigured in the terminal device or signaled tothe terminal device.

In an embodiment, the reception module 1102 is configured to receive amessage containing the TA granularity or range from the network device.

In an embodiment, the carrier comprises a plurality of BWPs, each BWP isassociated with a numerology, and the carrier has a referencenumerology, wherein the TA granularity or range is determined based onthe reference numerology and the reference numerology is a numerologywith the shortest CP length.

In an embodiment, a reference numerology assigned for terminal devicesunder an idle state is same in a cell.

In an embodiment, the terminal device 1100 further comprises an updatemodule (not shown) for updating a previous TA value considering thedifference of between an old TA granularity or range and a new TAgranularity or range; a calculation module (not shown) for calculating aTA compensation based on the new TA command and the new TA granularityor range; and a third determination module (not shown) for determiningthe TA value based on the updated previous TA value and the TAcompensation.

In an embodiment, a format of the TA command is same as a format of theTA command used in a wireless network supporting single numerologyoperation.

In an embodiment, a format of the TA command is different from a formatof the TA command used in a wireless network supporting singlenumerology operation.

In an embodiment, the format of the TA command changes in relation tothe TA command field length change.

In an embodiment, there is a correspondence between the format of the TAcommand and the TA granularity or range, the method further comprisesdetermining the format of the TA command based on the TA granularity orrange.

In an embodiment, the format of the TA command comprises an indicator ofthe TA granularity or range.

In an embodiment, the TA command is received together with uplink grantor a medium access control (MAC) command associated with uplink grant,wherein the TA granularity or range is determined based on a numerologyused for the UL grant or the numerology of PUSCH scheduled by the ULgrant.

FIG. 12 is a block diagram illustrating a telecommunication networkconnected via an intermediate network to a host computer in accordancewith some embodiments of the present disclosure.

With reference to FIG. 12, in accordance with an embodiment, acommunication system includes a telecommunication network 1210, such asa 3GPP-type cellular network, which comprises an access network 1211,such as a radio access network, and a core network 1214. The accessnetwork 1211 comprises a plurality of base stations 1212 a, 1212 b, 1212c, such as NBs, eNBs, eNBs or other types of wireless access points,each defining a corresponding coverage area 1213 a, 1213 b, 1213 c. Eachbase station 1212 a, 1212 b, 1212 c is connectable to the core network1214 over a wired or wireless connection 1215. A first UE 1291 locatedin a coverage area 1213 c is configured to wirelessly connect to, or bepaged by, the corresponding base station 1212 c. A second UE 1292 in acoverage area 1213 a is wirelessly connectable to the corresponding basestation 1212 a. While a plurality of UEs 1291, 1292 are illustrated inthis example, the disclosed embodiments are equally applicable to asituation where a sole UE is in the coverage area or where a sole UE isconnecting to the corresponding base station 1212.

The telecommunication network 1210 is itself connected to a hostcomputer 1230, which may be embodied in the hardware and/or software ofa standalone server, a cloud-implemented server, a distributed server oras processing resources in a server farm. The host computer 1230 may beunder the ownership or control of a service provider, or may be operatedby the service provider or on behalf of the service provider.Connections 1221 and 1222 between the telecommunication network 1210 andthe host computer 1230 may extend directly from the core network 1214 tothe host computer 1230 or may go via an optional intermediate network1220. An intermediate network 1220 may be one of, or a combination ofmore than one of, a public, private or hosted network; the intermediatenetwork 1220, if any, may be a backbone network or the Internet; inparticular, the intermediate network 1220 may comprise two or moresub-networks (not shown).

The communication system of FIG. 12 as a whole enables connectivitybetween the connected UEs 1291, 1292 and the host computer 1230. Theconnectivity may be described as an over-the-top (OTT) connection 1250.The host computer 1230 and the connected UEs 1291, 1292 are configuredto communicate data and/or signaling via the OTT connection 1250, usingthe access network 1211, the core network 1214, any intermediate network1220 and possible further infrastructure (not shown) as intermediaries.The OTT connection 1250 may be transparent in the sense that theparticipating communication devices through which the OTT connection1250 passes are unaware of routing of uplink and downlinkcommunications. For example, the base station 1212 may not or need notbe informed about the past routing of an incoming downlink communicationwith data originating from the host computer 1230 to be forwarded (e.g.,handed over) to a connected UE 1291. Similarly, the base station 1212need not be aware of the future routing of an outgoing uplinkcommunication originating from the UE 1291 towards the host computer1230.

FIG. 13 is a block diagram illustrating a host computer communicatingvia a base station with a UE over a partially wireless connection inaccordance with some embodiments of the present disclosure.

Example implementations, in accordance with an embodiment, of the UE,base station and host computer discussed in the preceding paragraphswill now be described with reference to FIG. 13. In a communicationsystem 1300, a host computer 1310 comprises hardware 1315 including acommunication interface 1316 configured to set up and maintain a wiredor wireless connection with an interface of a different communicationdevice of the communication system 1300. The host computer 1310 furthercomprises a processing circuitry 1318, which may have storage and/orprocessing capabilities. In particular, the processing circuitry 1318may comprise one or more programmable processors, application-specificintegrated circuits, field programmable gate arrays or combinations ofthese (not shown) adapted to execute instructions. The host computer1310 further comprises software 1311, which is stored in or accessibleby the host computer 1310 and executable by the processing circuitry1318. The software 1311 includes a host application 1312. The hostapplication 1312 may be operable to provide a service to a remote user,such as UE 1330 connecting via an OTT connection 1350 terminating at theUE 1330 and the host computer 1310. In providing the service to theremote user, the host application 1312 may provide user data which istransmitted using the OTT connection 1350.

The communication system 1300 further includes a base station 1320provided in a telecommunication system and comprising hardware 1325enabling it to communicate with the host computer 1310 and with the UE1330. The hardware 1325 may include a communication interface 1326 forsetting up and maintaining a wired or wireless connection with aninterface of a different communication device of the communicationsystem 1300, as well as a radio interface 1327 for setting up andmaintaining at least a wireless connection 1370 with the UE 1330 locatedin a coverage area (not shown in FIG. 13) served by the base station1320. The communication interface 1326 may be configured to facilitate aconnection 1360 to the host computer 1310. The connection 1360 may bedirect or it may pass through a core network (not shown in FIG. 13) ofthe telecommunication system and/or through one or more intermediatenetworks outside the telecommunication system. In the embodiment shown,the hardware 1323 of the base station 1320 further includes a processingcircuitry 1328, which may comprise one or more programmable processors,application-specific integrated circuits, field programmable gate arraysor combinations of these (not shown) adapted to execute instructions.The base station 1320 further has software 1321 stored internally oraccessible via an external connection.

The communication system 1300 further includes the UR 1330 alreadyreferred to. Its hardware 133S may include a radio interface 1337configured to set up and maintain a wireless connection 1370 with a basestation serving a coverage area in which the UE 1330 is currentlylocated. The hardware 1335 of the UE 1330 further includes a processingcircuitry 1338, which may comprise one or more programmable processors,application-specific integrated circuits, field programmable gate arraysor combinations of these (not shown) adapted to execute instructions.The UE 1330 further comprises software 1331, which is stored in oraccessible by the UE 1330 and executable by the processing circuitry1338. The software 1331 includes a client application 1332. The clientapplication 1332 may be operable to provide a service to a human ornon-human user via the UE 1330, with the support of the host computer1310. In the host computer 1310, an executing host application 1312 maycommunicate with the executing client application 1332 via the OTTconnection 1350 terminating at the UE 1330 and the host computer 1310.In providing the service to the user, the client application 1332 mayreceive request data from the host application 1312 and provide userdata in response to the request data. The OTT connection 1350 maytransfer both the request data and the user data. The client application1332 may interact with the user to generate the user data that itprovides.

It is noted that the host computer 1310, the base station 1320 and theUE 1330 illustrated in FIG. 13 may be similar or identical to the hostcomputer 1230, one of base stations 1212 a, 1212 b, 1212 c and one ofUEs 1291, 1292 of FIG. 12, respectively. This is to say, the innerworkings of these entities may be as shown in FIG. 13 and independently,the surrounding network topology may be that of FIG. 12.

In FIG. 13, the OTT connection 1350 has been drawn abstractly toillustrate the communication between the host computer 1310 and the UE1330 via the base station 1320, without explicit reference to anyintermediary devices and the precise routing of messages via thesedevices. Network infrastructure may determine the routing, which it maybe configured to hide from the UE 1330 or from the service provideroperating the host computer 1310, or both. While the OTT connection 1350is active, the network infrastructure may further take decisions bywhich it dynamically changes the routing (e.g., on the basis of loadbalancing consideration or reconfiguration of the network).

Wireless connection 1370 between the UE 1330 and the base station 1320is in accordance with the teachings of the embodiments describedthroughout this disclosure. One or more of the various embodimentsimprove the performance of OTT services provided to the UE 1330 usingthe OTT connection 1350, in which the wireless connection 1370 forms thelast segment. More precisely, the teachings of these embodiments mayimprove the latency and the power consumption, and thereby providebenefits such as lower complexity, reduced time required to access aceil, better responsiveness, extended battery lifetime, etc.

A measurement procedure may be provided for the purpose of monitoringdata rate, latency and other factors on which the one or moreembodiments improve.

There may further be an optional network functionality for reconfiguringthe OTT connection 1350 between the host computer 1310 and the UE 1330,in response to variations in the measurement results. The measurementprocedure and/or the network functionality for reconfiguring the OTTconnection 1350 may be implemented in software 1311 and hardware 1315 ofthe host computer 1310 or in software 1331 and hardware 1335 of the UE1330, or both. In embodiments, sensors (not shown) may be deployed in orin association with communication devices through which the OTTconnection 1350 passes; the sensors may participate in the measurementprocedure by supplying values of the monitored quantities exemplifiedabove, or supplying values of other physical quantities from which thesoftware 1311, 1331 may compute or estimate the monitored quantities.The reconfiguring of the OTT connection 1350 may include message format,retransmission settings, preferred routing etc.; the reconfiguring neednot affect the base station 1320, and it may be unknown or imperceptibleto the base station 1320. Such procedures and functionalities may beknown and practiced in the art. In certain embodiments, measurements mayinvolve proprietary UE signaling facilitating the host computer 1310'smeasurements of throughput, propagation times, latency and the like. Themeasurements may be implemented in that the software 1311 and 1331causes messages to be transmitted, in particular empty or ‘dummy’messages, using the OTT connection 1350 while it monitors propagationtimes, errors etc.

FIG. 14 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 12 and FIG. 13. Forsimplicity of the present disclosure, only drawing references to FIG. 14will be included in this section. In step 1410, the host computerprovides user data. In substep 1411 (which may be optional) of step1410, the host computer provides the user data by executing a hostapplication. In step 1420, the host computer initiates a transmissioncarrying the user data to the UE. In step 1430 (which may be optional),the base station transmits to the UE the user data which was carried inthe transmission that the host computer initiated, in accordance withthe teachings of the embodiments described throughout this disclosure.In step 1440 (which may also be optional), the UE executes a clientapplication associated with the host application executed by the hostcomputer.

FIG. 15 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 12 and FIG. 13. Forsimplicity of the present disclosure, only drawing references to FIG. 13will be included in this section. In step 1510 of the method, the hostcomputer provides user data. In an optional substep (not shown) the hostcomputer provides the User data by executing a host application. In step1520, the host computer initiates a transmission carrying the user datato the UE. The transmission may pass via the base station, in accordancewith the teachings of the embodiments described throughout thisdisclosure. In step 1530 (which may be optional), the UE receives theuser data carried in the transmission.

FIG. 16 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 12 and FIG. 13. Forsimplicity of the present disclosure, only drawing references to FIG. 16will be included in this section. In step 1610 (which may be optional),the UE receives input data provided by the host computer. Additionallyor alternatively, in step 1620, the UE provides user data. In substep1621 (which may be optional) of step 1620, the UE provides the user databy executing a client application. In substep 1611 (which may beoptional) of step 1610, the UE executes a client application whichprovides the user data in reaction to the received input data providedby the host computer. In providing the user data, the executed clientapplication may further consider user input received from the user.Regardless of the specific manner in which the user data was provided,the UE initiates, in substep 1630 (which may be optional), transmissionof the user data to the host computer. In step 1640 of the method, thehost computer receives the user data transmitted from the UE, inaccordance with the teachings of the embodiments described throughoutthis disclosure.

FIG. 17 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 12 and FIG. 13. Forsimplicity of the present disclosure, only drawing references to FIG. 17will be included in this section. In step 1710 (which may be optional),in accordance with the teachings of the embodiments described throughoutthis disclosure, the base station receives user data from the UE. Instep 1720 (which may be optional), the base station initiatestransmission of the received user data to the host computer. In step1730 (which may be optional), the host computer receives the user datacarried in the transmission initiated by the base station.

It is noted that any of the components of the network device andterminal device can be implemented as hardware or software modules. Inthe case of software modules, they can be embodied on a tangiblecomputer-readable recordable storage medium. All of the software modules(or any subset thereof) can be on the same medium, or each can be on adifferent medium, for example. The software modules can run, forexample, on a hardware processor. The method steps can then be carriedout using the distinct software modules, as described above, executingon a hardware processor.

The terms “computer program”, “software” and “computer program code” aremeant to include any sequences or human or machine cognizable stepswhich perform a function. Such program may be rendered in virtually anyprogramming language or environment including, tor example, C/C++,Fortran, COBOL, PASCAL, assembly language, markup languages (e.g., HTML,SGML, XML), and the like, as well as object-oriented environments suchas the Common Object Request Broker Architecture (CORBA), Java™(including J2ME, Java Beans, etc.), Binary Runtime Environment (BREW),and the like.

The terms “memory” and “storage device” are meant to include, but notlimited to, an electronic, magnetic, optical, electromagnetic, infrared,or semiconductor system, apparatus, or device, or any suitablecombination of the foregoing. More specific examples (a non-exhaustivelist) of the memory or storage device would include the following: anelectrical connection having one or more wires, a portable computerdiskette, a hard disk, a random access memory (RAM), a read-only memory(ROM), an erasable programmable read-only memory (EPROM or Flashmemory), an optical fiber, a portable compact disc read-only memory(CD-ROM), an optical storage device, a magnetic storage device, or anysuitable combination of the foregoing.

In any case, it should be understood that the components illustratedherein may be implemented in various forms of hardware, software, orcombinations thereof, for example, application specific integratedcircuit(s) (ASICS), functional circuitry, an appropriately programmedgeneral purpose digital computer with associated memory, and the like.Given the teachings of the disclosure provided herein, one of ordinaryskill in the related art will be able to contemplate otherimplementations of the components of the disclosure.

The descriptions of the various embodiments have been presented forpurposes of illustration, but are not intended to be exhaustive orlimited to the embodiments disclosed. Many modifications and variationswill be apparent to those of ordinary skill in the art without departingfrom the scope and spirit of the described embodiments.

1. A method for operating a terminal device, comprising: receiving atime advance, TA, command from a network device; determining a TAgranularity; and determining a TA value based at least partly on the TAcommand and the TA granularity, wherein different numerologies areconfigured for at least two carriers, wherein the at least two carriersserve the terminal device and the terminal device supports multiplenumerologies.
 2. The method according to claim 1, wherein the TAgranularity is determined by a numerology of the multiple numerologiesused by the terminal device, wherein there is a correspondence betweennumerology and TA granularity.
 3. The method according to claim 1,wherein the numerology comprises the subcarrier spacing, SCS.
 4. Themethod according to claim 1, wherein determining the TA value based atleast partly on the TA command and a TA granularity comprises: updatinga previous TA value considering the difference between an old TAgranularity and a new TA granularity; calculating a TA compensationbased on the new TA command and the new TA granularity; and determiningthe TA value based on the updated TA value and the TA compensation.
 5. Amethod for operating a terminal device, comprising: receiving a timeadvance, TA, command from a network device; determining a TAgranularity; and determining a TA value based at least partly on the TAcommand and the TA granularity, wherein the TA granularity is determinedby a numerology of multiple numerologies used by the terminal device,wherein there is a correspondence between numerology and TA granularity.6. The method according to claim 5, wherein different numerologies areconfigured for at least two carriers, wherein the at least two carriersserve the terminal device and the terminal device supports multiplenumerologies.
 7. The method according to claim 5, wherein the numerologycomprises the subcarrier spacing, SCS.
 8. The method according to claim5, wherein determining the TA value based partly on the TA command and aTA granularity comprises: updating a previous TA value considering thedifference between an old TA granularity and a new TA granularity;calculating a TA compensation based on the new TA command and the new TAgranularity; and determining the TA value based on the updated TA valueand the TA compensation. 9.-39. (canceled)
 40. A terminal device,comprising: a processor; and a memory, the memory containinginstructions executable by the processor, whereby the terminal device isoperative to: receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity, wherein differentnumerologies are configured for at least two carriers, wherein the atleast two carriers serve the terminal device and the terminal devicesupports multiple numerologies.
 41. A terminal device operative toperform the method of claim 2, wherein the terminal device comprises: aprocessor; and a memory, the memory containing instructions executableby the processor, whereby the terminal device is operative to: receive atime advance, TA, command from a network device; determine a TAgranularity; and determine a TA value based at least partly on the TAcommand and the TA granularity, wherein different numerologies areconfigured for at least two carriers, wherein the at least two carriersserve the terminal device and the terminal device supports multiplenumerologies.
 42. A terminal device, comprising: a processor; and amemory, the memory containing instructions executable by the processor,whereby the terminal device is operative to: receive a time advance, TA,command from a network device; determine a TA granularity; and determinea TA value based at least partly on the TA command and the TAgranularity, wherein the TA granularity is determined by a numerology ofmultiple numerologies used by the terminal device, wherein there is acorrespondence between numerology and TA granularity.
 43. A terminaldevice operative to perform the method of claim 6, wherein the terminaldevice comprises: a processor; and a memory, the memory containinginstructions executable by the processor, whereby the terminal device isoperative to: receive a time advance, TA, command from a network device;determine a TA granularity; and determine a TA value based at leastpartly on the TA command and the TA granularity, wherein the TAgranularity is determined by a numerology of multiple numerologies usedby the terminal device, wherein there is a correspondence betweennumerology and TA granularity. 44.-59. (canceled)